The present invention relates to evacuable storage containers, and in particular to filters for one-way valves used in such storage containers.
Collapsible, evacuable storage containers typically include a flexible, air-tight bag, an opening through which to place an article in the bag, and a fixture through which to evacuate excess air. A user places an article into the bag through the opening, seals the opening, and then evacuates the air in the bag through the fixture. With the bag thus evacuated, the article contained therein may be significantly compressed so that it is easier to transport and requires substantially less storage space.
Collapsible, evacuable storage containers are beneficial for reasons in addition to those associated with compression of the stored article. For example, removal of the air from the storage container inhibits the growth of destructive organisms, such as moths, silverfish, and bacteria, which require oxygen to survive and propagate. Moreover, such containers, being impervious to moisture, inhibit the growth of mildew.
Not only large, compressible items such as clothing may be stored in a collapsible, evacuable storage container. For example, it may be desirable to store bulk items made of small particles, such as powders or granulated resins, in an evacuated container. One situation that commonly occurs is that a particular bulk item is shipped in a large, rigid container such as a drum. Bulk items may be moisture sensitive and are sealed against moisture during shipment. But many times a user does not need to use the entire contents of the large container, and so once exposed to air the remaining bulk contents quickly become unusable and are thus wasted.
One collapsible, reusable, evacuable storage container is shown in the above-referenced U.S. Pat. No. 5,480,030 issued to Sweeney et al., under common ownership with the present invention, and incorporated herein by reference in its entirety. The ""030 patent discloses a one-way air valve assembly having a flexible diaphragm that seals against a valve seat. The valve assembly also has vanes positioned to prevent the bag material or bag contents from obstructing air holes or the diaphragm while air is being evacuated through the valve assembly. These vanes may protect against the bag material, or against large objects stored in the bag, but the vanes do not prevent small particles from entering the air holes and either blocking air holes or preventing the diaphragm from properly closing once evacuation is complete. Furthermore, small particles may be carried through the valve and become lodged in the vacuum producing device used to evacuate the storage container, thus affecting operation of the vacuum producing device.
Therefore the need exists for a reusable, collapsible, evacuable storage container that may store bulk items that include particles or granules.
Embodiments of the invention are directed to collapsible, evacuable storage containers. These storage containers have a one-way valve assembly allowing air to pass out of a flexible, air-tight bag, but not to return to the bag through the valve assembly. A filter is configured to be fitted against the one-way valve assembly so that material in the bag does not pass into or through the valve assembly when air is evacuated from the bag.
In one embodiment of the invention, the filter is made to be compatible with an existing one-way valve assembly. A filter assembly is formed of a cylinder capped by a top portion. The top portion has air slots through which air passes before entering the one-way valve assembly. A filter element is placed in the filter assembly so that air passing through the air slots is filtered. Embodiments of the invention may include filter elements providing filtration for various particulate sizes.
In an embodiment of the invention, the cylinder of the filter assembly contains a plurality of slots so that the filter assembly may be placed over radial vanes on the valve body. These slots are formed so that when the filter assembly is pressed onto the valve assembly, a seal is formed between the filter assembly and the vanes. In one embodiment of the invention, an annular lip is positioned at the base of the cylinder. This lip is configured to seal the filter assembly against a corresponding inner wall of the valve assembly.